TRENTON - At least four New Jersey schools had bomb threats Wednesday, causing evacuations and tense moments.

Three of those schools were in Passaic and a fourth threat was made in Montville.

While all of the threats turned out to be unfounded, school officials want anyone who might consider calling in a bomb threat to know that their actions are not harmless.

Passaic Mayor Dr. Alex Blanco warns would-be callers that the threats are not going to go unpunished.

"As a father of four boys and the mayor of Passaic, I feel strongly that any individual caught making false threats and disrupting our school children should be prosecuted to the full extent of the law," Blanco says.

School officials say they must treat each threat as if it was real, and that they cause huge disruptions to the school day. Police also say that resources such as bomb squads and fire trucks are taken away from where they could really be needed.

State police also say though that there is no penalty for calling in something suspicious, even if it turns out to be harmless.